South Urban Areas Research Articles

Spatial-temporal variability of PM2.5 air quality in Beijing, China during 2013–2018

This study investigates spatial-temporal variability and trends of ambient PM2.5 in Beijing, China, using data collected from eight urban and four suburban stations. During 2013–2018, the city-wide annual PM2.5 concentrations decreased significantly by 40% (84 μg/m3 in 2013 vs. 50 μg/m3 in 2018). The decreasing PM2.5 trend is more pronounced in winter and during the heating season (November–March), in urban areas, and at the median and upper percentiles of PM2.5 concentrations. The 95th percentile PM2.5 concentrations had decreased by 20 μg/m3/yr in the heating season and 16 μg/m3/yr in the non-heating season. During the six-year study period, there was a significant increase in excellent air quality days (PM2.5 concentration < 35 μg/m3) and a significant decrease in heavy pollution days (PM2.5 concentration > 150 μg/m3). PM2.5 concentrations were strongly correlated across the 12 stations. Urban areas in south Beijing experienced higher PM2.5 levels than suburban sites at every hour-of-day, day-of-week, and month-of-year. PM2.5 levels were higher during winter and the heating season, when PM2.5 emission was high due to space heating and mixing layer heights were low. PM2.5 was higher at weekends than during weekdays, when 20% of private passenger vehicles are prohibited, and higher at night than during the day, when heavy duty delivery vehicles are not permitted. These temporal and spatial trends suggest that Beijing's PM2.5 is strongly impacted by local emissions. Our results indicate, control strategies implemented were successful in Beijing's air quality improvement, but further reduction of PM2.5 concentrations in Beijing could be challenging due to significant contribution from its neighboring cities, calling for comprehensive and collaborative efforts in regional/national scale.

Countermeasures of Non-Point Source Pollution Prevention and Control in Wohushan Waterhead Area

Wohushan reservoir is an important drinking water source for south urban area of Jinan, however, the water quality of Wohushan reservoir is not safe, and agricultural non-point source pollution is the main reason that caused the water quality deteriorate. This paper analysed the sources of non-point source pollution through datum of population and agriculture production and other economic and social activities in Wohushan reservoir area. The water quality effect of domestic sewage, house refuse, live stock dung, and unreasonable use of fertilizer and pesticide were discussed as emphasis. Further more, the factors of the non-point source pollution were summarized according to policy, statute, economic, technology etc. At last, countermeasures of non-point source pollution prevention and control were proposed based on the source and pathway control of contaminates including perfect law system, strengthen policy guidance, increase funding, use fertilizer and pesticide reasonably, popularize biotechnology and methane tank, carry out efficient eco-agriculture construction, etc.

Clinical spectrum of rheumatic fever and rheumatic heart disease: A 10 year experience in an urban area of south

Background:Rheumatic fever (RF) is an important problem concerning developing countries like India. Rheumatic heart disease (RHD) is one of the most readily preventable chronic diseases.Aim:This study was done to find out the clinical profile, risk factors, compliance with treatment and outcome among RF/RHD cases so as to suggest better case management strategies.Materials and Methods:Clinical records of 51 RF and 71 RHD cases admitted in tertiary care hospitals in Mangalore between 2001 and 2010 were reviewed retrospectively.Results:Mean age of RF cases were 17.4 ± 12.1 years and RHD cases were 33.2 ± 18.6 years. More than half of RF and RHD cases were males. Commonest risk factors among RF cases were poor socioeconomic status (60.4%), history of upper respiratory tract infection before disease onset (58.8%) and undernutrition (35.3%). Commonest clinical manifestation among RF cases was fever 39 (76.5%) followed by polyarthritis 34 (66.7%). Commonest valvular lesions among RHD cases was mitral stenosis with mitral regurgitation found in 42.9% cases. Compliance of patients with prophylactic antibiotics was found to be 37 (30.3%). Mortality rate was significantly more among RHD cases (P = 0.0399).Conclusions:Improvement of socioeconomic and nutritional factors is an important task required for primary prophylaxis and of compliance for secondary prophylaxis of RF.

Modeling analysis of the impact of anthropogenic emission sources on ozone concentration over selected urban areas in Texas

Due to several regional–scale high ozone episodes that impacted the urban areas in south and central Texas over the past decade, the Texas Commission on Environmental Quality (TCEQ) has designated several urban regions as near non–attainment areas. A regional photochemical modeling experiment was set up to simulate a high ozone episode of September 11–14, 2002 in order to evaluate the impact of various anthropogenic emissions sources on ozone concentrations. The base case simulation showed reasonable model performance by capturing the peaks and the diurnal variability of observed ozone concentrations within the modeling domain. A comprehensive impact assessment of anthropogenic emissions from various source categories to the 8–hour ozone concentration was evaluated for each of the urban areas within the study region. Through a source apportionment analysis of emissions influencing the 8– hour ozone concentrations, NOx and VOC limited areas were identified. The model results showed that the net effect of all anthropogenic emissions was approximately 8.4 ppb in Victoria, 8.8 ppb in Corpus Christi, and 31.2 and 34.1 ppb in Austin and San Antonio, respectively. Impact of major emissions source categories differed regionally with ozone concentrations in Austin and San Antonio mainly influenced by mobile sources, while Corpus Christi and Victoria were largely impacted by long–range transport of ozone. On a local scale, Corpus Christi was also impacted by non–road sources, while Victoria was influenced by point sources. Ozone sensitivity analysis showed higher sensitivity towards VOC within the urban cores of Austin, San Antonio, and Corpus Christi, while the overall modeling regions showed higher NOx sensitivity. This would indicate that both NOx and VOC emissions reduction plans need to be developed and implemented for the mitigation of regional and urban ozone. The results also revealed that biogenic emissions played an important role in the urban regions of south and central Texas.

Preliminary study of patterns of medication use for depression treatment in China

This systematic review investigated drug utilization for depression and assessed trends in prescriptions in China. Major Western and Chinese electronic databases were searched without language restriction for studies reporting defined daily doses. A total of 76 studies published between 2000 and 2010 reporting data on prescriptions for depression in China between 1996 and 2008 were included. All studies were published in Chinese. Most trials were conducted in urban areas in south and east China. Twenty-nine drugs were reported as antidepressants. On the basis of defined daily doses, melitracen/flupentixol combination, fluoxetine, and paroxetine were the most frequently prescribed compounds. According to published evidence, selective serotonin reuptake inhibitors have become the most commonly prescribed class of antidepressant drugs in China.

Inflation of the Aira Caldera (Japan) detected over Kokubu urban area using SAR interferometry ERS data

Nine ERS-1 and ERS-2 descending orbit data ac- quired over Aira Caldera between June 1995 and November 1998 were used to create 36 differential interferograms. Al- though the interferograms exhibit a relatively low level of coherence, even for couples sampling short time intervals (6 months), Synthetique Aperture Radar (SAR) observations re- veal a distinct range change pattern over Kokubu urban area whose amplitude increases with the time separation between SAR images. The analysis of the ground deformation time series relative to the earliest ERS images showed a maxi- mum uplift of about 20 mm between the north and the south of the urban area during the period covered by our satellite observations. Taking the reduced surface of the coherent area into account, we performed a simple modeling of the defor- mation field assuming an inflating spherical source within an elastic half-space medium located beneath the centre of the Aira Caldera. This simple model predicts a maximum volume increase of 20-30◊10 6 m 3 between 1995 and 1998, which would produce an inflation of about 70 mm at the cen- tre of the Aira Caldera and 40 mm in the Kokubu south urban area. These results are in good agreement with other geo- physical observations carried out on the Aira caldera during this period. Despite the limited spatial extent of the coherent areas around the Aira Caldera, this study shows that Din- SAR method using data collected in C band can be success- fully used to detect subtle ground displacement changes of the volcanic complex and thus provides complementary in- formation to ground-based geodetic monitoring of dynamic processes of the Aira Caldera and Sakurajima volcano.

Black Homeplace Migration to the Yazoo-Mississippi Delta: Ambiguous Journeys, Uncertain Outcomes

Between 1910 and 1970, African Americans moved out of the southeastern U.S. in one of the largest movements in human history. Some estimates hold that more than 9 million black Southerners left the South for new lives in the North and West. The migration reached its peak in the 1950s, and began to slow in the 1960s. In the early 1970s, these black migrants and their descendants began coming home to the South, a trend that continues today. This study looks at one region to which many African Americans have returned, the Yazoo-Mississippi Delta. Regions like the Yazoo-Mississippi Delta have been largely ignored in black return migration studies. Much of the work that has been done to document the return migration of blacks to the South has focused on the South's urban areas. What has been neglected is the fact that there is also a significant return of African Americans to the rural South, a region of chronic economic stagnation. While the U.S. Census Bureau collects information on its long forms that can lead the researcher to a better understanding of African American migration processes and place attachments, the data are imperfect and can only provide the backbone of understanding. In an attempt to dig beneath the available data, we employ ethnographic methodology in this study. We focus on the geographic life history of Mrs. Dorothy Mae Scott.

A cluster randomised intervention trial of asthma clubs to improve quality of life in primary school children: the School Care and Asthma Management Project (SCAMP)

Aim: To evaluate the effectiveness of a programme of asthma clubs in improving quality of life in primary school children with asthma. Methods: A cluster randomised intervention trial was undertaken...

Does cutting of mugwort stands affect airborne pollen concentrations?

Pollen of mugwort (Artemisia vulgaris L.) is the most important allergenic pollen in urban areas of south and central Finland in late summer. The purpose of this study was to investigate, experimentally, whether the cutting of mugwort stands affects its airborne pollen concentrations. Experimental plots were either cut (4 plots) or uncut (4 plots) in 2 previous seasons: 4 of them were small (less than 0.5 hectare) and 4 large (greater than 5 hectares). Finally, the plots were divided randomly into 2 groups according to a third variable, cutting in the study season, 1989. Samples were taken on 2 rainless mornings at the peak mugwort flowering time. Two rotorod type samplers were used at heights of 1 and 2 m from ground level, simulating the inhalation heights of children and adults, respectively. The results indicate that cutting mugwort stands significantly reduces airborne pollen concentrations, but the treated areas have to be large, since in the town area there are plenty of mugwort pollen sources. The pollen concentrations at the 2 heights tested did not differ significantly.